Electric contact



J. B. CHEMIDLIN. AELECTRIC CONTACT. APPLlcAloN man APR. 13. v1921.

1,415,795. Patented May 9,1922'.

JOHNB. CHEMIDLIN, OF PLAINFIELD, NEW JERSEY.

ELECTRIC CONTACT.

Application led April 13, 1921.

To all whom t may concern Be it known that I, JOHN B. CHEMIDLTN, acitizen of the United States, and a resident of Plainfield, in thecounty of Union and State of New Jersey, have invented a new andImproved Electric Contact, of which the following is a full,clear, andexact description.

This invention relates to electric contacts and has for an object toprovide an improved construction wherein parts are ,provided which maybe connected to different articles so that when the articles are broughtinto certain relation to each other the contacts will engage and providea proper circuit.

Another object of the invention is to provide a contact which may beused in connec-` tion with removable signs, the arrangement being suchthat when the sign is applied the circuit is completed and when the signis `removed the circuit is opene In the accompanying drawing- Figure 1is a front view of part of a sign constructed to use one signillustrating how the invention may be used.

Figure 2 is a rear View of the sign shown y in Figure 1.

Figure 3` is a sectional view through Figure 1 on line 3 3. 0

Figure 4 isa substantially vertical section y through Figure 2 on line44.

` away Figure 5 is a top plan view of the letter shown in Figure 1 withcertain parts broken or illustrating. the `appearance of the springcontacts forming certain features of the invention.

Figure 6 is a bottom tact plate shown at Figure 4.

In many devices which use electrical en` ergy, connecting means must beprovided which will permit the devices to be applied and removed.Heretofore, in many devices, as for instance, in electric signs, socketsand plugs have been used because of their easy operation and readyadaptability or connec tion and disconnection. Where signs have beenused as that illustrated in the accompanying drawing, the plugs must beinserted before the letter and care must be taken to push the wiresoutof the way when the letter is placed in its correct position. Thisrequires considerable effort and care.

In the present invention, a contact has been provided which will permitthe letter l, for instance, to be properly placed in posiplan view ofthe con` the upper part of Specification of Letters Patent.

Patented May 9, 1922. Serial No. 461,129.

tion easilyand without any thought to the electric connection. Inotherwords, a person changing the letter l would merely have to remove saidletter and substitute another and the electric connection would takecare of itself so that the new letter would be properly `illuminatedwhen correctly positioned. The letterl is any suitable form oi letterand is provided with turned over edges 2 and 3 as shown in Figure 5whereby a covering 4 may be applied, said covering having` flanges 6 and7 which may be sprung back as shown by dotted lines in Figure 5 and thenforced under the flanges 2 and 3 This covering is intended to protectthe various `connections and wires associated with the sockets 8 in theletter l. This covering also carries a plate 9 of porcelain or otherform of insulation which in turn carries contact pins 1() and 11. Plate9 may be held by screws 12 or other suitable means while the contactpoints 10 and 11 are preferably solid rods having an enlargement 13 attheir inner ends as shown in Figure 4, said enlargement litting into atublar member 14 supporting a spring 1,5. The wirings of the sockets 8are connected in any suitable manner to the member 15, as for instance,by the con` necting members illustrated in Figure 6. By thisconstruction and arrangement. two contact plugs are provided which areresiliently held in a given position and, consequently, which will takeup any unevenness between the letter l and the casing 16 in which it ispositioned when .in use.

From Figure l it will be observed that the porcelain plate 9 .isprovided with a projecting boss 17 which extends through openings in theupper part of the cover 4l so as to prevent positively any shortcircuiting at this point. Arranged in the easing 16 is a porcelain orother insulating plate 18 having a boss 19 extending througha supportingsection 20. A cup-shaped member 21 rests against the boss 19 andsurrounds the lower end of the contact pin 22, which contact pin isrigidly held in the plate 18 by a nut or any other suitable means.Suitable conducting wires 23 and 24 are connected to the respective pins22 so that current is continuously supplied thereto and to theirrespective enlargements 2`5 located'in the cupshaped members 21. Whenthe letter l is placed in position the pins 1() and 11 willautomatically fit 'into the cup-shaped me1nbers 21 and press against theenlargement 25 so as to complete the electrical connection. In orderthat this connection may be maintained, the casing 16 is provided with agroove 26 at the bottom and a groove 2T at the top.

In inserting the letter l, the upper edge 28 of the front plate 29 ofthe letter is inserted into the groove 27 and-the letter is forcedupwardly until the lower edge 30 is able to move into groove 29. Thisupward movement is permitted by reason of the springs 15. -Ater the edge30 has moved into groove 26, the-letter is permitted to move downwardlyuntil the edge 3() strikes the bottom of groove 26 whereupon the partsare in the position shown in Figure et and the contacts 10 and ll arestill in engagement with the pins 22, To remove the letter it is onlynecessary to raise the same slightly and then swing the lower end out ashort distance. After this has been done, the letter may be loweredslightly and then moved away and ay new one substituted by inserting theupper edge of the letter lirst and then allowing the lower edge 30 todrop in the groove 26.

What I claim is l l. Ina contact or the character described a supportinginsulating plate, a pin arran'gedonsaid plate, acoacting plate, a

sprin pressed contact rod carried by said secon plate and an insulatingcup surrounding the end of said pin.

2. A contact structure comprising a pair of insulating plates, one oifsaid plates having apair of tubes therein, a spring arranged in each ofsaid tubes, a pin arranged in each oi said tribes and resiliently heldin a given position by said springs, the other of said plates having apair of pins having enlarged heads adapted to be engaged by therer-tiliently pressed pins and a cup surrounding said heads on one ,tacearound the edge, the walls of said cup projecting beyond said heads.

3. In an electric sign of the letter selective type, the combination ofa plate secured to the sign and a plate secured to the le ter, saidplates when in place lying opposite. each other, a plurality ofinsulatorsI associated with each plate, each insulator carrying aContact pin adapted to autmnatiwilly contact with the pins on theopposite plate when the letter is in its operative position` and`springs associated with the pins on the letter to keep said pinspressed against the pins on the sign when the letter is positionedwithin said sign.

JOI-IN B. GHEMIDLIN.

